Isuck at writing papers! can someone give an introductory paragraph on a halloween party?

First you have to know what kind of paper you are writing. IF it's an argumentative paper, than you need to find something involving Halloween parties to argue about. Maybe you would want to argue against Halloween parties, making the claim being that they only encourage unhealthy eating. Or you could argue for them, saying that these parties create community and bring people together, providing fun safe activities that families can enjoy together. 

Well then start by defining your terms. Make a general assumption about the kind of people likely to show up at a Halloween party. you can divide them into groups based on their characteristics and their traits, like the people who dress up versus those who don't. Then you can explain in following paragraphs why and how you classified them into these categories. also in a following paragraph you can detail the motives of why classification of these groups is important. you could also divide them up into sub-categories. Such as for those who dress up: do they dress up as something scary or something funny? finally in your conclusion you can restate your classifications by paraphrasing your topic statements of each paragraph.